Seats including mechanisms for providing adjustment of the inclination of the seat cushion and the vertical position of the seat cushion above the base of the seat are known in the art. In this regard see U.S. Pat. Nos. 2,609,029; 2,792,873; 2,795,267; 2,942,647; 3,147,945; 3,165,351; 3,552,707; 3,662,984; 3,692,271; 4,190,225; 4,222,543; and 4,247,071.
Some of these patents also teach hand-operated levers and associated mechanisms and components employed for positioning and moving the seat longitudinally. See U.S. Pat. Nos. 2,792,873; 2,795,267; 3,147,945; and 3,662,984. See also U.S. Pat. No. 3,659,895 which teaches an actuating handle and associated mechanism and components which are used to actuate rotational movement of a seat assembly about a vertical axis and longitudinal movement of the seat both forward and backwards with respect to the vheicle.
However, each proposal taught suffers some disadvantage, for example, sloppiness, noise during operation, cost of manufacture and complexity of assembly and operation. By way of example, the structure taught by U.S. Pat. No. 4,190,255 is noisy to operate, sloppy and expensive to manufacture, being more suitable for use in heavy-duty off-road equipment where there is not concern for "seat chucking", sloppiness and noise of operation.
It is therefore an object of this invention to provide an improved seat assembly and mechanisms therefor for use to adjust the position of the seat cushion of a seat providing improved adjustability of the inclination of the seat cushion, and the vertical position of the seat cushion above the seat base of the seat. In this regard, the seat is more easily adjusted without noise, sloppiness and complexity of assembly and operation, whether the rear of the seat cushion is positioned higher or lower than the front of the seat cushion or the vertical height of the seat is raised or lowered.
It is a further object of this invention to provide an improved hand-operated lever and associated mechanism and components therefor which are used to actuate longitudinal movement of the seat and to adjust the inclination of the seat cushion (to position the rear of the seat cushion higher or lower than the front of the seat cushion) and the vertical position of the seat cushion above the base.
Further and other objects of the invention will be realized by those skilled in the art from the following summary of the invention and detailed description of an embodiment thereof.